The microcosm: ontogeny. The macrocosm: cosmic history, human
history, organic development. This comparison may be the most
durable analogy in the history of biology (Kleinsorge, 1900). It seems,
to use another ontogenetic metaphor, as inevitable as aging.

I have chosen, for this book, just one of these pervasive comparisons
—that between stages of ontogeny and a sequence of adult organisms, either created or evolved. As Haeckel's biogenetic law, this
comparison provided an argument second to none in the arsenal of
evolutionists during the second half of the nineteenth century. Moreover, the relation envisaged by Haeckel and, in a very different
manner, by the earlier Naturphilosophen transcended mere analogy
to become an intimate and necessary causal connection. Yet the basic
argument is as old as recorded biology; in pre-evolutionary thought,
its formal treatment as an analogy played an important role in the
systems of men as different in time and belief as Aristotle and Charles
Bonnet. Its appearance in Aristotle as an argument for epigenesis
offers no surprise and testifies only to its antiquity; on the other hand,
its role in the preformationism of Bonnet—a system that would seem
to deny not only phylogeny but ontogeny as well—attests to its
remarkable ubiquity.

The analogy of individual to cosmic history was favored by many
pre-Socratic thinkers. The nascent cosmos of Anaximander, Anaximenes, and Democritus was surrounded by an envelope resembling
the amniotic membrane (Wilford, 1968, p. 109). Empedocles' cos-